Patent DE-19910279-A1 (DE)
Title: Bearing disk support structure for the rotor shaft of the spinning rotor at an open-end spinner has an offset of the rotor shaft axis towards the disk support gap with support surfaces giving low friction and wear protection
Inventor: WASSENHOVEN HEINZ-GEORG
IPC: D01H4/10
Filed: 1999-03-09
Abstract: The assembly of disks, as a bearing support for the rotor shaft of an open-end spinner, has the position of the support disk bearing set in relation to the static bearing component (27) of the axial bearing (18) so that the center axis (51) of the rotor in the support gap between the disks is offset towards the disk gap. The surface of the static component (27) towards the support disks (54), outside the magnet/pole disk assembly (41-43), has a surface layer (40) which reduces friction and protects against wear. It covers an angle of at least 45 deg  at the side of the bearing away from the roller gap as a support surface, at a gap from the rotor shaft in operation. The gap is max. one-half of the smallest gap between the pole disks and the ferromagnetic straps (45,46).  The support surface (40) is on a replaceable ring insert (39) within a bearing bush (28) as a passage for the rotor shaft (4) in the axial bearing (18). Or the ring insert is of a material with low friction and wear protection. The ring insert (39) has a radial adjustment to give either an equal ring gap against the rotor shaft (4) or a narrower ring gap on the side away from the bearing support disk gap. A support surface (49'), at an axial gap from the end (48) of the rotor shaft, is also of a low friction and wear protection material. A further support surface (49) is at the level of the end (48) of the rotor shaft (4), towards the bearing disk gap and displaced from the shaft end when in operation, of a low friction and wear protection material. The support surfaces (49',49) are formed by a sleeve (49) of a low friction and wear protection material, held in an opening. The low friction and wear protection material is of carbon fibers or graphite. The ratio of the offset between the center axis (51) of the rotor shaft (4) and the static bearing component (27) to the difference between the inner dia. of the pole rings (42,43) and the outer dia. of their facing straps (45,46) is between 1:3 and 1:8 and pref. 1:4 to 1:6.5. The offset of the center axis of the rotor shaft against the center axis of the static bearing component is 0.2-1.0 mm and pref. 0.25-0.4 mm. A wear reducing coating on the rotor shaft (4) is restricted to the section (44) outside the axial bearing (18). The ratio of the outer dia. (D) of the permanent magnet rings (41) to the inner dia. (d) is between 1.5:1 and 2.8:1 and pref. between 1.7:1 and 1.8:1. The ratio of their width (m) to the width (b) of the outer pole rings is between 2.5:1 and 5:1 and pref. between 3:1 and 3.9:1 and a ratio to the width (B) of a pole disk between the permanent magnet rings is between 1.3:1 and 2.5:1 and pref. between 1.5:1 and 2:1. The width (b) of the outer pole disks is 0.5-1.5 mm, and the width (B) of the pole disk between the permanent magnet rings is 1-3 mm. The widths (B,b) match the widths of the aligned ferromagnetic straps (45,46) in the gaps of the non-magnetic fillings (47) in the rotor shaft (4). The permanent magnet rings are rare earth magnets. All the facing edges of the pole disks (42,43) and straps (45,46) are unrounded. The rotor shaft (4) has a constant dia. along its whole length. Or the rotor shaft dia. at the axial bearing is smaller than the dia. of the remaining shaft length by one-eighth to one-half of the shaft dia., and pref. one-quarter to three-eighths of the standard shaft dia. It is fitted with inserts (47) so that the static bearing components (27) maintain the gap width between the pole disks (42,43) and the straps (45,46). The insert (47) depth is 0.1-0.3 times the strap dia.